MACHINE A FAIRE UNE TRESSE SANS FIN DE TABAC DECHIQUETE POUR MACHINE A CIGARETTES

APPARATUS FOR FORMING A CONTINUOUS CUT TOBACCO BRAID IN A CIGARETTE MAKING MACHINE

Abrégé anglais

ABSTRACT OF THE DISCLOSURE
An apparatus for forming a continous cut tobacco braid
in a cigarette making machine, comprises:
- a transfer duct (1) for transferring by means of a
suitable air stream the cut tobacco from the delivery end
of a cut tobacco feeder (2, 3) to an endless belt type
braid forming suction tape (5);
- a first pneumatic collecting duct (12, 112) which
receives the tobacco ribs, from the delivery end of the
tobacco feeder, and conveys them into a collecting box
(13);
- a second pneumatic collecting duct (22, 122) which
receives the excess tobacco trimmed from the tobacco braid
formed on the underside of the suction tape (5) and conveys
it into the feeding hopper (103) of the tobacco feeder
(2, 3);
- a deflector valve (14) arranged between the first
pneumatic duct (12, 112) for the tobacco ribs and the
second pneumatic duct (22, 122) for the trimmed excess
tobacco. The deflector valve (14) is switchable from a
first position in which the tobacco ribs are conveyed
through the first pneumatic duct from the delivery end of
the tobacco feeder into the collecting box, and the trimmed
excess tobacco is conveyed through the second pneumatic
duct to the feeding hopper of the cut tobacco feeder, to a
second position, in which the cut tobacco delivered by the
delivery end of the cut tobacco feeder, including the
tobacco ribs, is returned into the feeding hopper (103),

while the suction is stopped in the duct (22) receiving the
trimmed excess tobacco, and the suction is also stopped in
the duct (112) leading to the tobacco ribs collecting box
(13);
- sensor means (27, 28) arranged at the interior of the
tobacco transfer duct (1), sensitive to the formation of
tobacco obstructions and operatively associated with a
control circuit for switching the deflector valve (14) and
for interrupting the air stream at the interior of the
transfer duct (1).

Revendications

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. Apparatus for forming a continous cut tobacco braid
in a-cigarette making machine, comprising:
- a transfer duct (1) for transferring by means of a
suitable air stream the cut tobacco from the delivery end
of a cut tobacco feeder (2, 3) to an endless braid-forming
suction tape (5);
- a first pneumatic collecting duct (12, 112) which
receives the greater and heavier tobacco particles, such
as tobacco ribs, from the said delivery end of the said
tobacco feeder, and conveys them into a collecting box (13);
- a second pneumatic collecting duct (22, 122) which
receives the excess tobacco trimmed from the tobacco braid
being formed on the under side of the said braid-forming
suction tape (5) by suitable trimmers (21) arranged along
the path of the said suction tape (5) dowstream of the
said transfer duct (1), for conveying said trimmed excess
tobacco into the feeding hopper (103) of the said cut
tobacco feeder (2, 3);
- a deflector valve (14) arranged between the said
first: pneumatic duct (12, 112) for the tobacco ribs and the
said second pneumatic duct (22, 122) for the trimmed excess
tobacco, said deflector valve (14) being switchable from a
first position in which the tobacco ribs are conveyed
through the first pneumatic duct from the delivery end of
the tobacco feeder into the collecting box, and the
trimmed excess tobacco is conveyed through the second
pneumatic duct from the trimmers to the feeding hopper of

the cut tobacco feeder, to a second position in which the
cut tobacco delivered by the delivery end of the cut
tobacco feeder, including the tobacco ribs, is returned
into the feeding hopper (103) of the cut tobacco feeder,
while the suction is stopped in the duct (22) receiving
the trimmed excess tobacco, and the suction is also stopped
in the duct (112) leading to the tobacco ribs collecting
box (13);
- sensor means (27, 28) arranged at the interior of the
tobacco transfer duct (1) said sensor means being sensitive
to the formation of tobacco obstructions or concentrations
at the interior of the said transfer duct (1), said sensor
means being operatively associated with a control circuit
for actuating control means for switching the said
deflector valve (14) and for interrupting the air stream at
the interior of the transfer duct (1).
2. Apparatus according to claim 1, in which the sensor
means comprises a light emitting source (28) arranged on
one side of the cut tobacco transfer duct (1) and a
cooperating photoelectric cell (27) arranged on the other
side of the said transfer duct.
3. Apparatus according to claim 1, in which the said
deflector valve is operated by means of a double-acting
pneumatic piston and cylinder unit.

Description

!1 1 6 ~
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5~111-1AII~ or ~
The pre~en~ invention relaté~ to a~ apparatus for
... . .
~orming a continuous cut tobacco braid in a cigarette
.. ~ . . . . .
maki~g mac~iine~ IJsually~ a~ apparatu~ of thi~ type
compri~e~ a cu~ tobacco deli~ery fro~t, ~Rhich ~upplie~ th~
cut tobacco to an a~cending t:rans:f er duct ~hlch c~nveys
the ~obacco~ entrained in a~ cending sl;re~m o~ air, to
the under~ide of ~ endle~ ~3uction tape~ ~here the
tobacco braid is formed~ After the ~ormatiorl o:E the tobacco
braid g which contai~ tobacco in e~cce~s, the said tobacco
braid i8 ~ubjected to the actio~l of a trimmer~de~lce" which
trim~ off the ~aid exce3s tobacco. The trimméd e~ccess tobQcco
i~ then recycled to the tobacco hopper~ which :Eeed~ the
delivery frorlt .
In apparat-a~3e~ of the described type~ there ex~t~ the
possibilit;r of formation, in the upwardly directed tra~sfer
duct~ o~ ob3tructio~s of cut tobacco9 which may cau~3e
conge~tioD3 a~d jammings in the trarlsfer duc~ with con~3equen,t
di~turb~noe~3 in the operatio~ of the cigarette making
machine ~,
I:n order to timely stop the appara~:us a~d remc~e said
ob~t~ctions: be~ore the~ completely jam the trarlsfer duct~,
the i~ention proposes ~n automatic device whieh comprise~
a sensor arr~nged in the ~aid transfer duct, in a zone in
~hich it i~ most probable the formation o~ a cut tobacco
obstruction9 the said se~E;or being se~3iti~e to the initial
~Orm2tiO~l oi~ an obstruction i~ such a ma~ner as to stop the
ci~Sarette making machi~e~ a~ al80 to ~top the stream of

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air in the tran~fer duct) while at t~e same time it put~
into operatlon à pneumatic duct which recycles into the
tobacco feeder the cu~ tobacco ~hich co~tinue~ to be ~ed to
the transfer duct, duri.ng the time ~hich i~ requested b~
the cigarette maki~g machine for it~ completé stopp~ng
(which i~ not ~n~tantaneous~. In this manner~ the cut tobacco
ob3truc~io~ in the tran~fer duct is timely dete~ted, stopp2d
~nd can be easily removed, thu~ limiting the ~topping time o~
the cigarette making machi~e.
~ he above an~ other *eatures o~ the invention, and the
ad~antage~ deri~ing there~rom~ ~111 appea~ evident from the
following det iled da~criptio~ o~ a preferred embodiment,
made by ~ay of non-limiti~g example, with reference to ~he
attached drawing~
BRIEF DES~RIP~ION OF ~HE DRAWINGS
Figure 1 is a diagrammatic Yide elevatlon view ~hich
show~ a transfer duct ~or transferring`the cut tobacco from
the delivery end of a tobacco ~eeder to the suction tape
of the tobacco braid forming line, said tran~fer duct beirlg
prorided with a device ~or detecting ~nd ~topping the
~ormatio~ o~ to~acco obstructions at it~ interior.
Figure 2 sho~ns in section, in an enlarged ~cale, a
detail o~ the de~lector ral~e employed in the apparatus
according to the invention.
~ igure 3 i~ a ~ection, in an enlarged ~cale, according
to line~ III of Figure 1, and ~ho~ a detail relating
to the photocell type ~ensor u~ed for aetecti~g the cut

8 :~ 2 6 ;
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.
to~acco ob5tructio~3 i:ll the tranqfer duct~
~igure 4 i~ a section accordillg to line IV-IV OI
Fig~are 30
. . . . . ........ . . .
DESORIPTIt)N ûF ~HE PREFERRED E~BODIMENT
. .
~ ith referencè to the drawings, the pneumàtic transfer
duct compri~e~ for e.:campleg~ a ~-shaped duct o:f the type
illustrated i~ the ~.S. patent NoO 4 041 959 (&arro~e~.
~he said T-~haped duct 1 provides to the transfer of the
cut tobacco from the delivery end (which i~ transversal to
the working line of the oigarette making machine) o~ the
belt 2 of the cu~ tobacco feeder 3 ~hich u~ually compri~es
a carding drum 4)~ to the endless belt braid-formi~g
suction tape ~ of the tobacco braid ~ tobacco rod forming
line 6 o~ the cigarette making machine~ At the interior of
the said ~ shaped duct 1 there is created and maintained an
ascending air stream ~he ~low o~ ~hich i~ ~uitably adju~ted,
in such a manner a~ ~o entrai~ upwardl~ the cut tobacco
delivered from belt 2~ while the greater and heavier tobacco
parts~ such as the ribs 7~ are separated from the cut
tobacco due to their impact against the angle plate 8 (see
Figure 1)o Xn the normal operation of the c~garette making
machi~e9 the said tobacco rib~ 7 fall inside a trou~h 9
from ~hich they are con~eyed to the suction mani~ola 10
.
through 8tar v~lve 11~ ~rom the manifold 10 the said rib~ 7
are engaged and carried by the air stream existing at the
i~terior of the ~uction duct 12, l12 and are discharged from
the ~aid duct (under normal operational conaitions of the
machine~ i~to the pneumatic collecting box 13, by pas3ing

2 ~
. .
through the deflector valve 14 in its l'~traight" po~ition~
a~ illustrated in Figure 2,
~ t the interior of the T-shaped duct 1 there is created
and maintained an ascending stream o~ air due to the
combined suction exerted through the suitable grid 15 at
the top of the duct itsel~ (see ~igure 3) by the suction
manifo~d 16 controlled through the throttle valve 17, and
due to the s~etion exerted through the permeable tape 5.
~ he cut tobaccoJ as above mentioned, is engaged and
carried by the~.said ascending air stream and is caused to
be deposited on the underside of the suction tape 5 which
closes the hood 18 at the top of the said ~-shaped duct 1.
The thus deposited cut tobacco ~orms a uniform layer 19 o~
a predetermined thickness 9 presenting a predetermined
exceeding non uniform portion 20~ ~he said exceeding portion
20 i9 trimmed off by the rotary trimmers 21 and the di~card
or exce~s tobacco (iOe. the tobacco removed by the trimmer~
is ~ucked by the ~uction duct 22, 122 which recycles it to
the hopper 103 o~ the tobacco feeder 3. ~ore particularly,
the pneumatic duct 22, 122 discharges the excess tobacco
insids the ple~u~ chamber 23 from which chamber thè said
exce~ tobacco ~all~ into the said hopp~r 3 throu~h the
star valve 240
~ he suction ducts 12~ 112 and 229 122 are operatively
as~ociated between each other by mean~ of the deflector
valve 14, comprising the paired ~witch flap~ 114, 214
which are controlled at ~ill, for example by a double-acting
pneumatic cylinder 25~ ~der normal condition~ of operatio~
of the cigarette maXing machi~e, the deflector 14 i8 po~itioned

2 ~;
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. .
in the not-commutated position illustrated i~ Figure 2~ in
which both ducts 12, 112 ~nd 227 122~are under suctio~ and
the duct 12 9 112 disGharges the tobacco ribs into the
pneumatic box 13~ while the duct 22~ 122 conve~ the exces~
tobacco ~0 back to the hopper 103 of the tobacco feede~ 3~
During the said normal conditions of operatio~, at the
interior o~ the pneumatic transfer duct 1~there may be ~ormed
progressively cut tobacco obstructions which, ~he~ever they
are le~t free to grow so as to rau~e a jamming of the said
transfer duct.g will cau~e long stops.of the machine for
their removal~
~ suallyt in a transfer duct 1 of the type illustrated,
these ob~tructions tend to be ~ormed in the~zo~e indicated
by ~he reference numeral 26 correspo~ing to the downstream
end o~ the stem of the T~sha~ed duct, ju~ below the suction
~ape 50
I~ order to avoid such irlconveniences, in the æone 26 of
initial fo~mation o~ the ~obacco obstruction, there is
arra~ged a sensor device, preferab].y of the photoelectric
type~ 9uch-a~ for example a photocell 27 and a light emitting
~ource 28~ arranged respecti~ely at each ~ide of the transfer
duct 1 ~see particularly ~igure 3 ) .
The photoelectric cell 27 i~ mounted in a co~Yentional
co:ntrol circuit (not illustrated) which controls, with time
delay ~if neces~ary) ~ the clo~ure of the throttle valve 17
and the switching o~ the deflector val~e 14 from its normal
po~itio~ (Figure ~) ~o the commutated position sho~qn i:n
Figure 1~ in which there i~ topped the suction in the
de~cending duct 22 while the trimmers 21 are al~o stopped

: : ;
toge~her with the cigarette making machine, following ts
the operatio~ o~ the control circuit~ ~he suction is al~o
stopped in the branch duct 122 leading to the pneumatic
~ox 13 which receives the tobaceo ribs~ while a suctio~
stream i esta~lished through the ducts 12 and 122 ~o as to
.. . . .
co~ey back i~to the hopper 103 all the cut tobacco which is
discharged by the delivery belt 2 still for~a-certain ~ime
period after the ~topping o~ the ascending suction stream
through the ~- haped duct 1~ i~ co~sideratio~ of the fact
that the ~toppi~g o~ the cigarette m~king-machine is not
i~tantaneo~O
Due to t~e fact that the tape 5, although stopped, is
mai~tained under ~uction~ the gravity force-will not be
~uf~icient by itself for causing the downfall of the occlusion
26, so that ~aid occlu~io~ will have to be removed manually~
However? in consideration of the fact that the de~ice
according to the i~ven~ion detects and ~tops at their ~ery
starting the obstructions, the occlusion produced by them i~
very limited and c~n be removed i~ a short time. ~herea~ter,
the ~igarette m~king machine can be again started, after
having open~d the throttle valve 17 and s~lvitched the deflector
Yalvè ~4 to the :~lorm~? po~ition sho~n in ~igure 2.
It ls believed that the inve~tion will haYe bee:~ clearly
under~tood from the foregoing detailed description of a
preferred embodiment. Changes in the details of eonstructi.on
may be re~orted to ~ithout departing from the spiri~ of the
invention, and it i~ accordingly intended that no limitation
be implied and that the hereto annexed claim~ be gi~en the
broade~t interpretation to which the employed language fairly
adm~tsO